Release notes for the IOLAN DS Family Device Server

To see the build version for your software, in CLI mode, enter the command "version".

You should only upgrade to this version of firmware if your product was not shipped
with this version AND you require to use one or more of its features.

All of the fixes are automatically rolled into the next release version.

Version 4.8, 4.8 F



·         Web Manager runs as a non-root task.

·         Updated OpenSSL to version 1.0.2g.

·         Updated OpenSSH to version 7.2p2.

·         Updated NTP to version 4.2.8p6.

·         Updated USB Mode-switch to version 2.3.0

·         Updated Mini http to version 1.23

·         Added new SSH ciphers, AES-CTR, AES-GCM and ChaCha20-poly1305.

·         Added new SSL encryption AES-GCM, key exchange ECDH-ECDSA, HMAC SHA256, SHA384.

·         Added SSL version TLS1.1 and TLS 1.2.

·         Added CLI commands to delete keys and certificates.

·         Added 5 more IP filtering ranges.

·         Added support for RTS toggle on serial ports.

·         Can now disable IP forwarding between Ethernet interfaces.

·         Can now configure the PPP echo requests.

·         Increased the size of the serial port name to 30 characters.

·         Increased the size of the TACACS secret to 30 characters.




·         The IOLAN rack units were vulnerable to NTP amplification attacks.

·         Multi host TCP sockets would not allow to hosts to connect is SSL is enabled on the FIPS firmware.

·         The http tunneling stops accepting new tunnel requests.

·         The PPP connection will disconnect during a large file transfer.

·         The virtual modem serial port does not toggle ring indicator signal.

·         There was data lost when using NFS remote port buffering.

·         Would stop accepting new TCP multi host with SSL connections.

·         The telnet command from the terminal port profile would not support binary pass-through.

·         Two IOLANs connected with serial tunneling would sometimes drop the character before a break signal.

·         The serial tunneling server will send out an extra byte out the serial port when it receives a set modem signal mask that is hex 0xFF.

·         SSH allows people to do TCP port forwarding.

·         Multisession does not work correctly if IP aliasing is configured.

·         The Web Manager cannot transfer keys using TFTP or SFTP.

·         Using Device Manager through an http tunnel to transfer files does not work.

·         A TCP raw sessions largest packet was 512 bytes.

·         The IOLAN stops processing Modbus requests from multiple Modbus masters.

·         The IOLAN DS1 data logging buffer size is not configurable.



Version 4.7



·         Support for WIFI on SDS1 W, SDS2 W and SDS4 W models.



Version 4.6, 4.6 F



·         Added the ability to reset the serial port statistics.

·         Made a number of security improvements

o    Internal user database can provide a 10 second delay after an invalid authentication attempt. After 5 successive incorrect authentication attempts within 1 minute the user will be locked out for 5 minutes.

o    Internal user database could allow each user to only be logged into the system once.

o    Internal user database can enforce passwords to be at least 8 characters long with at least one number.

o    The Web Manager can stop the web browser from caching.

·         PPP can now authenticate with TACACS+ using CHAP.



·         Removed a deadlock condition in Modbus slave gateway.

·         TruePort keep alive timer would cause disconnects if data was in only one direction.

·         LPD printing now supports source TCP port greater than 1024.

·         TruePort tcflush command could lock up the IOLAN.

·         Port idle timeout not working all the time.

·         Speed up connection time for secure HTTP Tunnels.

·         TruePort lite mode TCP connection resets sometimes.

·         Console mode power command (control p) sometimes disconnects the session.

·         L2TP/IPSec connection to a Windows 7 client behind a NAT router will disconnect on its own.

·         IPSec would not work over a modem connection if the connection was not up when IPSec first started.

·         Http tunnel server would sometimes show the wrong tunnel name for a connection.

·         If busy enough, Modbus slave gateway only responds to one of the devices.

·         Memory leak in Http Tunnels if not configured correctly.

·         IPSec would stop working if the IP address of the default gateway changes.

·         Http Tunnel client would sometimes not be able to connect to the server.



Version 4.5, 4.5 F



·         Added support for TruePort  (v6.6) for Windows to support the Windows IOCTL_SERIAL_SET_XOFF system call.

·         Only allow IP traffic to/from a range of IP addresses.

·         Modbus Slave Gateway IP Aliasing allows multiple requests to devices on different serial ports to be processed at the same time.


·         System memory lost when HTTP Tunnel connection goes up and down.

·         A TCP Sockets serial port using Multihost would stop receiving data if it received data during the system boot.

·         Disable Strict Host Key checking did not work when connecting to an internal serial port using SSH.

·         Could not connect to a Console Management serial port using the IP loopback address ( and TCP port (10001) if any serial port had an IP Alias address.

·         Could not connect to the Web Server (TCP port 80) through a HTTP or HTTPS Tunnel.

·         The IOLAN Desktop models with 1 or 2 ports will stop responding because of a system memory leak.  It did not happen with the DB-25 model.

·         TruePort full mode running at 300 bps would not work when the application did a tcdrain.  This only happened on IOLAN Rack models.

·         Modbus Slave would not process a request from the Modbus TCP master if the request did not come in one TCP packet.

·         The IOLAN would not callback a PPP client.

·         SNMP monitoring (UDP traffic) through a HTTP Tunnel would stop after a while.

·         Secure file transfer would not work through a HTTP Tunnel if it was configured using the Web Manager.

·         Opening and closing a TruePort COM port through a HTTP Tunnel could cause the open to fail sometimes.  It would take 60 seconds before recovering.

·         TCP Modbus requests with a read length greater than 61 registers would cause an error for some Modbus TCP Masters by breaking the response into two TCP packets.

·         The Web Manager does not show the correct SNMP Trap privacy algorithm.



Version 4.4, 4.4 F



·         Support for USB wireless modems in the PCI slot.

·         Enhanced configuration for NTP/SNTP authentication to allow a different Key ID for the secondary host.

·         Increased the size of the LDAP Base field to 128 characters.


·         Errors on Web Manager Keys and Certificates page.

·         Units lose their configuration information.

·         UDP service type could lose data if it received data on multiple serial ports at the same time going to the same host and there was no ARP table entry.

·         SNMP MIB II Interfaces object “IfOperStatus” was incorrect.

·         No CLI command to disable SSH client strict host checking.

·         PPP dial in using the internal modem may not connect after a quick disconnect if the idle timeout is enabled.

·         Improved the reconnect time for the UDP service type.


Version 4.3.G4, 4.3.F4



·         Enhanced NTP/SNTP authentication to allow a different Key ID for the secondary host.


·         System memory lost when a SNMP message authentication failure happens.



Version 4.3 , 4.3 F


·         Enhanced data logging support.

o    Configure the size of the buffer

o    Eliminate data loss when the connection is lost

·         Vmodem phone number table host name support allows FQDN.

·         TCP MTU configuration.

·         Support for KTI 500F Rev B Fibre card.

·         TCP timeout and retry count configuration.

·         TFTP over HTTP Tunnel support.

·         Enhanced NTP/SNTP support

o    NTP client on Rack units and SNTP client on Desktop units.

o    Authentication using MD5 or SHA1 on all secure units.

·         SSH client strict host checking configuration.

·         SSH server grace login time configuration.

·         TCP Sockets profile now supports IP Aliasing with Multiple hosts.

·         Remap Modbus master ID to Slave ID

·         Option to not forward a byte with a receive error from the serial port.



·         Clustering would sometimes show slave units multiple times.

·         Cannot turn beak on/off from CLI.

·         Port Email alerts do not work unless server Email alerts are enabled

·         SSH banner is not being displayed

·         Desktop unit may lockup if the Ethernet link goes down at the same time as data is being transmitted.

·         SNMP security issue, improper HMAC validation allows authentication to be bypassed.

·         HTTP tunnel may be slow on some complex web pages.

·         IP UDP Multicast packets are only sent out on the first Ethernet interface.

·         EasyPort Web, Java Script, would not work on dual Ethernet units if Lan bonding was enabled.

·         The connection was resetting every couple of seconds using serial tunneling between two units.

·         PPP dial in using the internal modem may not connect after a quick disconnect.

·         Radius secondary host access rejected after the primary host goes down.

·         Increased the Maximum packet size for Modbus for 256 to 512 bytes.

·         IOLAN CLI Serialt debug tool crashes while capturing a large amount of data.

·         EasyPort Web connect button always uses HTTP to connect to the slave unit.

·         SNMP set port parity does not work correctly.

·         The Fibre card settings are lost when using the Device Manager text configuration file.

·         Proxy Arp PPP connection will stop working if the Ethernet interface goes down then up.

·         Cannot make multiple TCP Sockets connections if the listen port is greater than 32,767.

·         Modbus Slave port will not work if it receives data before a poll form the Modbus Master.

·         Snetsave and Snetload CLI commands would not work through an HTTP Tunnel.

·         Modbus Serial Master would send exception messages when configured not to.

·         IOLAN would lose Ethernet connectivity after sending a large number of SNMP trap messages.

·         TACACS would not work if a ‘#’ character was used in the secret.


Version 4.2 F


·         Introduces support for a special FIPS-140 version of the firmware. The FIPS version of the firmware will be designated as v4.2.F while the non FIPS firmware will continue to be designated as v4.2.G. Some options are not supported in the FIPS version due to the fact that they do not meet the strict security requirements imposed by FIPS. These include such items as encryption algorithms which are not deemed sufficiently secure for FIPS

·         The IOLAN can now be configured to not respond to IP Ping request messages.


·         The IOLAN one or two port units could lock up if there was traffic while the Ethernet interface went up and down.

·         Fixed a security issue with SNMP.


Version 4.2


·         Introduces support for new IOLAN models.

o    STS8-D desktop unit with 8 RS-232 serial ports.

o    SDS8C, SDS16C and SDS32C rack units with multi protocol serial ports with Cisco pin out.

·         Enhanced SNMP trap support.

o    Supports type v2c and v3 messages.

o    Supports inform type trap messages.

·         Support for Secure File Transfer Protocol (SFTP) to transfer files.

·         The OEM login feature now supports a custom login and password prompt.

·         TCP Sockets service type now supports the IP alias feature.

·         Two new CLI commands to allow the customer to fine tune the TCP keep alive time.

o    "set server monitor-connection-timeout" sets the time between TCP keep alive messages (was 5 seconds).

o    "set server monitor-connection-number" sets the number of unanswered TCP keep alive messages before the connection is closed (was 5).


·         The IOLAN internal modem would sometimes not answer an incoming call.

·         The Multihost feature would stop sending data to all the hosts if one of the hosts stopped responding.

·         The Vmodem feature would not parse the init string after an AT&F command.

·         The Serial Tunnel sometimes sent out extra characters after the DSR signal dropped.

·         The Clustering feature did not work if the second Ethernet port was connected and the first Ethernet port was not connected.

·         The break signal duration for Console Management was changed to 0.1 second from 1 second.

·         Secure ID authentication using a fully qualified domain name required the DNS server to be available when the IOLAN first boots up.

·         Internal GSM modems failed to connect to the network at locations with low signal strength.

·         SNMP trap messages for the IO units had the wrong value.

·         Static IPv6 addresses were lost if the Ethernet link went down.

·         The internal KTI fiber card was not detected.

·         The Vmodem feature would not parse the command line past the AT&F.

·         The Serial Tunnel could lose characters at slow baud rates when the RTS signal drops.

·         Very large fragmented messages over a SLIP connection could lose data.

·         PPP call-back with the IOLAN internal modem did not work.

·         HTTP Tunnelling did not work if the host address was a fully qualified domain name.

·         The IOLAN internal modem would only answer a call the first time.

·         Serial Tunnelling may lose the last character if the TCP connection drops quickly.


Version 4.1


·         HTTP tunneling - Provides the ability to establish connections to serial and LAN devices sitting behind a firewall or NAT router.

·         Support for the following Fiber PCI cards

o    Gigabit Fiber - KTI Networks, KG-500F

o    Fast Fiber – Transition Networks, N-FX-SC5-02

·         Ping Watch Dog – Ability to monitor IP hosts via PING requests and power cycle hosts if they are non-responsive

·         SMTP authentication – For Email notification, added support for various authentication methods with the Email servers.

·         MSCHAP – Support for MS-CHAPv1 and MS-CHAPv2

·         Introduction of new SNMP MIBs which correct a number of compilation errors as well as introducing MIB entries for the SNMP traps. Pre release 4.1 MIBs are supported by this release and will function as they did on previous releases.

·         Microsoft Active Directory – Enhanced the LDAP feature to fully support Microsoft Active Directory.

·         RFC2217 – Additional control for the handling of “break” signals

·         Session strings – Ability to send configured text strings to an attached serial device on session start/end.

·         Port ID – Ability to send a “port ID” string to a LAN device upon connection to the serial device.

·         Enhanced EasyPortWeb – Ability to select between using a “Java app” or “Java script” when connecting to a serial device via a browser.

·         Default server name – The previous default of “localhost” has now been replaced with “IOLAN-xxxxxx” where xxxxxx are the last 6 digits of the MAC address of the unit. This more clearly identifies a non-configured unit when discovered by the Device Manager.


·         Electric Utility models have been enhanced to now support “Dual Ethernet”. Previous models had a single Ethernet port. This release enhances the existing models by adding a second Ethernet port to all Electric Utility models.


·         Corrected filter for TCP ports 2601, 2602 and 2603. Filter should only prevent connection attempts to these ports but was preventing any message with that source from reaching the TCP stack.

·         Vmodem did not work correctly if the dialed phone number included a space and the user configured the phone number to IP mapping with the space.

·         On a DHCP renew of a lease, the IOLAN was not processing parameters such as DNS servers or gateways. Only the IP address information was being processed.

·         Corrected a “task prioritization” issue which affected performance under load conditions (especially in low latency mode of operation).

·         RPS (Remote Power Switch) would sometimes not apply the correct settings to the power plugs after a reboot of the power switch.

·         Can now SSH to a Fully Qualified Domain Name (as opposed to an IP address).


Version 4.0


·         This release introduces the "Electrical Utility" models to the IOLAN DS family of products. These units are designed to operate in more demanding industrial locations specifically electrical sub-stations. The new models are;

o    SDS8C HV - 8 serial ports, single power supply.

o    SDS8C DHV - 8 serial ports, Dual power supply.

o    SDS16C HV - 16 serial ports, single power supply.

o    SDS16C DHV - 16 serial ports, Dual power supply.

o    SDS32C HV - 32 serial ports, single power supply.

o    SDS32C DHV - 32 serial ports, Dual power supply.

·         When using HTTPS to configure the IOLAN, the user can now select a "reduced graphics" mode of operation. This greatly improves the time it takes to paint "complicated" screens.

·         This release introduces the ability for the user to provide their own custom landing page when pointing their browser to the IOLAN DS.

·         This release introduces the ability for the user to supply a custom SNMP MIB for the IOLAN unit. This MIB will co-exist with the standard IOLAN DS MIB.

·         When logging invalid login attempts, the log entry will now include the IP address of the client attempting the invalid login.


·         For desktop 1 and 2 port models, an issue has been addressed which caused EIA485 half duplex connections to sometimes not work reliably.

·         Corrected an issue with using "Internet Explorer" to configure an IOLAN, specifically the "vmodem" phone table. If you opened/closed (repeatedly) the "vmodem" phone table, garbage entries would appear.

·         Fixed an issue which prevented the IOLAN from issuing a subnet directed broadcast for the UDP service.

·         The probe for valid DNS servers was changed to send out IPv4 (not IPv6) requests when looking for an IPv4 DNS host.

·         Improved the Device Manager's ability to discover IOLANs when running on the "Vista" operating system.


Version 3.7


·         Introduction of two new models. These models have galvanic isolated serial ports and are complient with IEC-60601-1 standard. The new models are;

o    IOLAN MDC04 - Medical Device Concentrator, 4 serial ports.

o    IOLAN MDC08 - Medical Device Concentrator, 8 serial ports.


·         When the console port of SCS48 device is configured for hardware flow control the unit will not complete the boot sequence unless a terminal is attached and powered on. Terminal no longer needs to be present for the unit to complete the boot.

·         Under some extreme throughput conditions, serial data received on the serial port would be held for a few seconds before being forwarded on the LAN. This delay has been removed.

·         If you edit a UDP profile, set the direction to "serial to LAN", you are unable to enter the port number.

·         The unit will now correctly flush all data from the serial port when instructed to do so by Trueport.


Version 3.6


·         Added GUI support for Microsoft Special Administration Console (SAC)

·         Added support for Radius attributes NAS-Port-Id, NAS-IP-Address, NAS-Port, Calling-Station-Id, NAS-Identifier, NAS-Port-Type, NAS-IPv6-Address, Framed_Route,Class, Login-IPv6-Host, Framed-IPv6-Route, Login-IP-Host, Connect-Info

·         Added the ability to save/load text based configuration files using WebManger or CLI.

·         Added to ability to provide a User defined Factory Default Configuration file

·         Added the ability to access EasyPort with an admin user

·         Added support for MOTD to be displayed on the WebManager login screen

·         Added support to display a “generic” WebManager login screen

·         Added the Digital I/O extension feature which allows a digital input signal to be connected to digital output(s) or a TCP/IP Application over an IP network


·         Hunt groups now work with Trueport

·         Able to determine if a TCP Socket connection has an active TCP connection

·         Large file transfers in both directions using Trueport would sometimes not complete


Version 3.5


·         Added native VPN support for Microsoft XP using L2TP.

·         Added VPN exception configuration ability.

·         Added IPv6 support to many of the features in all IOLAN models, including DHCPv6. Also added IPv6 router advertisement (SDS/STS/SCS models only) capability.

·         Added the ability to configure IPv6 tunnels.

·         Added the ability to create routes/gateways through IPv6 tunnels, PPP-configured serial ports, and SLIP-configured serial ports.

·         Added data logging capabilities to the TCP Sockets and TruePort profiles.

·         Added ability to determine how the 'admin" user gets authenticated.

·         Enhanced the UDP Sockets profile configuration window to make it easier to configure.

·         Updated the TACACS+ and RADIUS dictionaries to control clustered port access.


·         Serial ports will not close before the data is completely sent.

·         Multicast packets using UDP can now be sent successfully through routers.

·         The IOLAN will now boot up successfully when the Hardware Speed and Duplex settings are set to a value other than Auto.

·         You can now send port buffering data to syslog without configuring an NFS server.

·         You can now manually enter multiple virtual modem (vmodem) commands separated by a space.

·         You can now set the S12 virtual modem (vmodem) register to 0 (zero) and actually get a delay of 0 (no delay).

·         Under certain conditions, the modbus gateway would not respond to future requests if a slave UID was non-responsive to the master gateway polling.

·         The IOLAN now responds immediately when monitor DCD and DSR signals are dropped. Also, any pending data is forwarded when the DCD or DSR signal is dropped.

Version 3.4


·         Added VPN capability using the IPsec protocol.

·         Added SNMP V3 user security options.

·         You can now download a PPP secrets file to the Device Server to support PPP CHAP or PAP authentication.

·         Enhanced the Port Buffering feature to allow keystroke logging and the ability to send port buffering data to syslog.

·         Users accessing the Device Server from the network can now enter a Telnet or SSH command (to connect to a host) after a successful login to the Device Server.

·         The number of times a user can attempt to login to the Device Server from the network is now governed by the Password Retry Limit parameter.


·         The modem dial string now sends the prefix ATD (before it sent ATDT).

·         The documentation for the 1-port DB9 model has been corrected to indicate that line termination required J1 and J9 to be jumpered.

·         Data can now be obtained from active Modbus slaves when a Modbus slave on the serial line stops responding to being polled (Modbus TCP/IP to serial gateway).

·         When using serial tunnel client and server mode to connect the serial ports of two Device Servers, RTS will no longer go inactive before all the data has been sent on the output side even though the CTS signal was dropped after the data on the input side.

·         PPP now supports dial in/dial out and will automatically install a default gateway using the PPP connection.

·         SNMP now supports network addresses in the Host field to allow any SNMP manager residing on a network that matches the community to access the Device Server.

Version 3.3


·         Improved the usability, design, and appearance of the WebManager and DeviceManager.

Version 3.2


·         Improved the likelihood that a serial application which was written to communicate to a directly attached serial device will operate correctly when connected to the serial device via a Perle Device Server. This includes back to back IOLAN DS setups as well as TruePort connections.

·         Improved the time it takes to re-establish connections after connection loss.

·         Ability for multiple hosts to access a single serial port via TCP has been added. This capability is available via the silent raw, reverse raw, and TruePort service types.

·         New modes of operation have been added to customize behaviour on a line basis. The new modes are:

o    Minimize latency

o    Optimize network throughput

o    Prevent message fragmentation

o    Custom packet forwarding

·         Enhanced the ability of the DeviceManager to discover and manage units. This can now be done over routers as well as when the DeviceManager and Device Server are on the same physical network but are logically configured on different IP networks.

·         IP address assignments performed via the DeviceManager will no longer be temporary.

·         Added ability for customer to define their own "factory default" configuration.

·         Vmodem service type has been enhanced to provide additional modem functions. Also added the ability to define a phone table to IP address lookup for modem applications which can’t be easily modified to specify an IP address instead of a phone number.

·         Added support for local MOTD (Message Of The Day).

·         Added I/O channel support for EasyPort Web.

·         Improved the accuracy of the system clock.

·         Ability to enable/disable DHCP for each Ethernet interface.

·         Serial tunnel mode has been enhanced to provide a much better throughput.

·         When defining hosts, user can now specify an IP address or a Fully Qualified Domain Name.

·         Added support for Microsoft direct connect PPP, host and guest.

·         Ability to initiate LAN connections based on "any data" being received on the serial port or a specific character being received on the serial port.

·         Added ability to accept UDP messages on any UDP port (as opposed to a specific port).

·         Ability to configure when secondary authentication method will be used. (i.e. only if first authentication host is unreachable or always).

·         Added a visual indication on Desktop models to alert the user when the unit is operating in "console" mode (flashing green Power/Ready LED).


·         DeviceManager was unable to find units if "active standby" was configured.

·         Fixed issue where sessions would be unresponsive when dialing into the built in modem after a hang-up of a previous session.

·         Fixed issue which caused SDS4 units not to respond to IPV6 pings.

·         Fixed an issue where a line configured for SLIP and EIA-422 was unable to transmit data.

·         Fixed issue preventing "dslogin" service type from working on the SCS modem.

·         Fixed an issue which caused a line configured for PPP to only connect once. A kill line was required to establish a new connection.

·         Improved DHCP timeouts to allow units to communicate with remote DHCP hosts. This requires greater timeouts since connection to DHCP host are sometimes over slow WAN links.

Technical Note

·         DeviceManager is now Vista compatible. If you want to use the online help that comes with DeviceManager, you need to follow the link and download the Winhelp viewer available for Vista from the Microsoft website.


Version 3.1


·         For SDS/SCS/STS models, clustering has been added to allow users to access Device Servers through a Master Device Server.

·         For SDS/SCS/STS models, support has been added for the new Perle Remote Power Switch (RPS) product, which allows users to securely manage power to devices plugged into the RPS.

·         EasyPort web has been added as a web browser access method to Device Servers in a cluster group, to Device Servers with Reverse Telnet or Reverse SSH ports using the supplied Java client, and to manage RPS plugs.

·         Dynamic DNS with support to automatically update when the Device Server's IP address changes or to automatically update when a PPP session is established.

·         For SCS models, support for wireless WAN cards in the PCI slot.

·         For SCS models, LAN active standby, which will automatically reassign the IP address for Ethernet1 to Ethernet2 if Ethernet1 should stop responding.

·         Ability to access a port/line by either its configured name or IP address.

·         Ability to automatically update a network DNS server with a DHCP assigned IP address for the Device Server.


·         The 4800 baud rate has been fixed to work on an SDS4.

·         When the Server parameter Single Telnet is enabled, Reverse line sessions will now close correctly.

·         Reverse Raw sessions will no longer refuse a connection for a period of time when they are opened, polled for data, and then closed again in fairly fast succession rates.

Version 3.0


·         New 1-port DS and SDS serial models: Analog Input, Relay Output, Digital I/O, and/or Temperature Input. The I/O models can communicate via a customized API to a serial Modbus application directly through the serial port or over the LAN using TruePort. A TCP Modbus application can communicate directly to I/O over the LAN. You can also enable I/O status UDP broadcasts.

·         As part of the I/O model line, serial pins can be configured for Digital I/O.

·         Added client-initiated functionality for TruePort, designating the TruePort host to initiate a connection to the Device Server.

·         Added custom baud rates for TruePort and the serial interface.

·         Added a system watchdog which allows the Device Server to automatically recover when a critical error condition is detected.


·         On a port configured for DSlogin with "monitor DSR" enabled, toggling DSR on and off every few seconds caused the port to "lock up".

·         Space parity did not work when connecting with Windows TruePort.


Version 2.4


·         Added support for Modbus.

·         Added the ability to make custom applications that can run on the Device Server using the Perle Application SDK. This can be downloaded from the Perle website at:

·         Added the Serial Tunnel Line Service to support RFC 2217.

·         Added TACACS+ support so that your TACACS+ server can now set user parameters on the Device Server.

·         Added Packet Forwarding to the Line Service options, so you can now control the definition or size of the serial data packet being sent to the network from the Device Server.


·         Changed the default behaviour of DHCP, so that it is now disabled by default.

·         Resolved the PPP LCP authentication issue when the Line Dial mode was set to None.

·         Resolve an issue where a character would be echoed back on a serial port before any line service had openned the serial port.

·         The VModem Line Service has been modified to allow a separator character, comma or semicolon ( , or ; ), after the ATD command string, before the numeric dial string (IP address).

Version 2.2.3


·         Added support for two new models: SCS48 and the SCS48 DAC.

Version 2.2


·         Added support for two new models: TS2 and SDS3M. See the User's Guide for more information.

Version 2.1


·         When connecting to TruePort for Solaris, the session sometimes failed to connect.

·         Fixed PPP IP address negotiation. When dialing Out with Address Negotiation enabled and the local IP address set to 0, the Device Server did not use the negotiated local IP address.


Version 2.0


·         Added support for many new rack mount models: STS, SDS, and SCS various port models. See the User's Guide for more information.

·         SSH-1 was added to the SSH server settings, so now users can access the Device Server via SSH-1 or SSH-2.

·         SSH-1 password authentication was added to the SSH server settings.


·         Using a reverse raw session for printing, data was lost if the session went down before all the data was received by the serial device.


Version 1.4 (SDS and SCS only)


·         Added support for 4-port SDS and SCS models.


·         Added the option of using a colon (:), in addition to the existing period (.) and semicolon (;), as a separator IPv4 address and the port number for Vmodem.

·         Fixed a TCP security problem on Linux.

·         Changed how Vmodem works, added a carriage return (CR LF) before the response, in addition to the carriage return that already existed after the response; this; this makes the Vmodem implementation closer to the standard.

Version 1.3


·         Combined the features created in Version 1.1 and Version 1.2, on both the
1-port and 2-port models.

·         Added 28800 to the serial port baud rates.


·         When a session is ended and a new session is started using the Reverse Raw line service, data from the previous session could be seen.

Version 1.2


·         Initial release of the 2-port SDS model, based on Version 1.0.x (therefore, no SSL/TLS support in this release).

·         Added the IOLAN+ look-and-feel interface for the 2-port SDS model.

·         Added Dial Timeout and Dial Retry parameters.

·         Added a Default User with a system password so users can long into the Device Server as a guest user and inherit the Default User settings.

·         You can now disable the ports on the 2-port model.

Version 1.1


·         SSL/TLS support added to the SDS 1-port model.

·         In the DeviceManager and all other configurators, inherited service type values were added for DSLogin. This is actually a functional clarification of how DSLogin inherits the settings for the Service type.


·         Resolved Device Server lockup, which occurred under certain circumstances when using the Device Server with TruePort in Full mode.

·         Using the UDP service type, the WebManager and the DeviceManager configurators will not let you configure the device server port (DS Port field).

·         Using the Reverse Raw service type, data can be lost when the connection disconnects quickly.

·         Corrected a problem with trueport full mode for Sun Solaris.

·         Corrected a problem with TruePort Full mode. Setting a baud rate of 0, resulted in the loss of other terminal settings.

·         When the Device Server is writing to flash (firmware upgrade etc.), the Power/Ready LED now flashes yellow and green.

·         Corrected a problem with the user service type TCP_CLEAR and IPv6.

·         Corrected a problem with the user service type TCP_CLEAR; the session was initiated with the wrong destination TCP port.

·         Corrected a problem in authentication for Reverse Raw sessions.

·         Improved latency.

·         Corrected an issue for Reverse Raw, Reverse SSH, and UDP sessions. If the data packet received on the LAN side was more than 128 bytes, only the first 128 bytes were transmitted on the serial side.

·         Corrected problem with reverse sessions. If the 0x00 (null character) was received from the network side, it was not immediately sent to the serial port; it was transmitted when the next byte was received.

·         Enabled generation of break signal on DS model for reverse telnet sessions.

·         Corrected issue where a PPP link would not re-connect if abnormally disconnected.

·         Corrected problem with a Reverse Raw session not passing certain control characters.

·         Corrected problem with RIP MD5 authentication.

·         Corrected problem with TruePort for AIX.

Version 1.0


Initial release of the 1-port DS and SDS models. See the User's Guide for more information.